6,777 research outputs found
Embryonic exposure of chicken chicks (Gallus gallus domesticus) leads to heightened sensitivities towards the exposed scent
In chickens, food consumption can be altered by exposing the chicks to scents as embryos. We exposed eggs to an orange-scented food additive in the final days of incubation. Following hatching, we tested these exposed chicks’ ability to detect this scent at a variety of concentrations. We found that orange-exposed chicks responded to an orange-scented solution at lower concentrations than control chicks. This sensitization may allow chicks to be more effective at locating acceptable food items but requires further testing to determine its significance. Orange-exposed and control chicks were also tested with the scent of raspberry. Orange-exposed chicks responded to the raspberry presentation significantly more than the control chicks did, suggesting that the embryonic exposure to orange may have influenced how the chicks responded towards another fruity smell. This result suggests that chicks may be learning general characteristics of exposed scents while in the egg, though this needs further research
Fabricación computacional
Ryan Hughes, doctorando de la escuela de Arquitectura de la Univesidad de Aarhus en colaboración con Zaha Hadid Architects y Odico Robotics, ha impartido la conferencia “Fabricación computacional” en la Escuela de Arquitectura de Málaga dentro de las jornadas con motivo de la semana cultural.
El ponente trató el tema de la innovación en la práctica arquitectónica, especialmente en relación al diseño computacional y la fabricación digital, a través de los proyectos de investigación en los que ha participado, así como su experiencia con diferentes encargos profesionales desde la consultoría de la que es fundador, Axis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Distribution of Stamped Dressel 20 Amphorae Produced at Axati in Roman Baetica: A Quantitative Study of Olive Oil Consumption Levels at Military and Civilian Sites
The Roman province of Baetica in southern Spain produced vast amounts of olive oil during the first three centuries CE. The small town of Axati is situated in an area now known as Lora del Rio along the Baetis River, the modern Guadalquivir. This town exported large amounts of olive oil which was distributed throughout the Roman Empire from northern Britain to Alexandria. This study will look at the stamped olive oil amphorae, Dressel 20 type, which were produced there and transported throughout the Empire. The distribution and consumption levels evidenced by these stamped amphorae are quantified here in order to compare the amounts consumed by military and civilian populations. Through this comparison it is demonstrated that the primary consumers were the city of Rome and the civilian settlements withm the frontier provinces
Approximating the inspiral of test bodies into Kerr black holes
We present a new approximate method for constructing gravitational radiation
driven inspirals of test-bodies orbiting Kerr black holes. Such orbits can be
fully described by a semi-latus rectum , an eccentricity , and an
inclination angle ; or, by an energy , an angular momentum component
, and a third constant . Our scheme uses expressions that are exact
(within an adiabatic approximation) for the rates of change (,
, ) as linear combinations of the fluxes (,
, ), but uses quadrupole-order formulae for these fluxes.
This scheme thus encodes the exact orbital dynamics, augmenting it with
approximate radiation reaction. Comparing inspiral trajectories, we find that
this approximation agrees well with numerical results for the special cases of
eccentric equatorial and circular inclined orbits, far more accurate than
corresponding weak-field formulae for (, , ). We
use this technique to study the inspiral of a test-body in inclined, eccentric
Kerr orbits. Our results should be useful tools for constructing approximate
waveforms that can be used to study data analysis problems for the future LISA
gravitational-wave observatory, in lieu of waveforms from more rigorous
techniques that are currently under development.Comment: 15 pages, 5 figures, submitted to PR
The Archaeology of a Colchian Landscape: Results of the Eastern Vani Survey.
This dissertation examines rural settlement patterns around the 1st millennium BCE site of Vani in Western Georgia (ancient Colchis) through the presentation of the results of a new intensive archaeological survey. Beginning in the 8th to 7th centuries BCE and extending into the Hellenistic Period, Vani grew to become an important place in the Colchian landscape. Evidence from the 7th-1st centuries BCE in particular, points to the emergence of a wealthy elite and suggest growing political and religious authority at the site. Unusually well-preserved and showing evidence for the emergence of strong political authority and increased contact with peoples living on the borders of Colchis, Vani has become one of the most important sites for reconstructing ancient Colchian society in the 1st millennium BCE.
The Eastern Vani Survey (EVS) was developed as an intensive survey component of the larger Vani Regional Survey project to examine an area to the east of the ancient site that had hitherto been little explored archaeologically. The main goals of the project were to better understand rural settlement to the east of Vani, to evaluate and characterize the level and complexity of social organization in the environs of the site and to use this new data to contextualize previous research on Vani and its region.
The data recovered by the Eastern Vani Survey, combined with previous research in the area, revealed that settlement to the east of Vani was dispersed with particular places in the landscape serving as focal points of communal and/or elite activity. The most important of these places are Mshvidobisgora, Gabelauri, Isriti, Kveda Bzvani and Kveda Gora. The survey has also made it clear that a good deal of the increase in Classical and Hellenistic ceramic material evidenced in the region is tied very closely to developments at Vani and suggests an expanded use of ceramics. Though these developments are very related to changes in population in the region between the 7th-1st centuries BCE, the ceramic data from the survey alone does not allow a quantification of that growth.PHDClassical Art and ArchaeologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113352/1/rchughes_2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/113352/2/rchughes_1.pd
Determination of Glacial-Ice Temperature Profiles Using Radar and an Antenna-Gain Estimation Technique
Knowledge of glacial ice temperature profiles is important to the study of glaciology. Currently, the only method of obtaining ice temperature profiles is by drilling ice cores, which is a long and arduous process. Fortunately, ice-penetrating radar can be used to obtain temperature profiles without the need of ice cores. A radar technique incorporating common mid-point geometries is presented for measuring ice temperature. However, in order for this technique to work, accurate estimates of the far-zone antenna gain within glacial ice are necessary. Currently, commercial electromagnetics software packages utilizing the finite element method (FEM) are used by academia and industry to accurately characterize antennas in free space, and near finite dielectric and conductive materials. Unfortunately, these commercial packages are incapable of accurately determining the far-zone antenna gain near a dielectric half-space such as glacial ice. Therefore, to solve this problem, a routine for determining the far-zone gain of an antenna located near glacial ice was developed, which utilizes an FEM package in conjunction with a near-to-far-field transformation (NFFT). Additionally, glacial ice imposes another complication to estimating far-zone antenna gain: the dielectric constant is a function of depth. Therefore the far-zone antenna gain within glacial ice changes as a function of depth due to increased ray bending resulting from refraction. To solve this problem, the geometric optics technique (GO) was used to propagate the far-zone antenna gain determined within the relatively shallow upper region of glacial ice, dubbed the quasi-far-zone, to any depth within glacial ice. Results are presented showing that this technique is capable of accurately determining the far-zone gain at any depth within glacial ice for an arbitrary antenna located near glacial ice. Additionally, results are presented showing that with the aid of this numerical antenna gain estimation software, ice-penetrating radar can be used to determine glacial ice temperature profiles at all depths
Modeling and Optimization of a Novel Chilled Ammonia Absorption Process and Amine-Appended Metal-Organic Frameworks for CO2 Capture
Post-combustion capture is one of the leading technologies for CO2 abatement from anthropogenic sources which have contributed significantly to the rise of atmospheric greenhouse gases. Specifically, solvent-based capture post-combustion processes are the industry standard but can suffer drawbacks such as high energy penalties and corrosion. In this work, two possible improvements are investigated which have been recently proposed in the literature. The first is aqueous ammonia as a capture solvent which has been shown to have several advantages including, but not limited to, a lower regeneration energy. The second is a novel solid sorbent, an amine-appended metal-organic framework (MOF). The MOF exhibits several promising attributes, namely, a step-shaped adsorption isotherm which leads to lower working capacities and lower regeneration energies when compared to traditional solid sorbents. The overall goal of this work is to develop rigorous mathematical models which can be used for process design and economic evaluation of these technologies.
First, an integrated mass transfer model is developed for the chilled ammonia process (CAP). This model is developed using a simultaneous regression approach that has been recently proposed in the literature with parameter estimation performed using data from a pilot plant source and wetted-wall column. The optimally estimated parameters are shown to have a lower prediction error to validation data than parameters found in literature. The integrated mass transfer model is then used to develop a model for a novel chilled ammonia process. The process includes a NH3 abatement system which utilizes a reverse osmosis membrane to aid in separation and reduce the energy penalty. Simulation of the process shows that the membrane can significantly reduce the energy requirement of the reboiler, condenser, and cooler in the abatement section. Uncertainty of the estimated mass transfer parameters is quantified using a fully Bayesian approach which is demonstrated to show a significant reduction in the prediction uncertainty of key process indicators.
Second, isotherm and kinetic models are developed for amine-appended MOFs, dmpn-Mg2(dobpdc) and Mg2(dobpdc)(3-4-3). The step-shaped adsorption isotherms exhibited by these MOFs present a modeling challenge since many of the traditional isotherm models are unable to capture step transitions. Three isotherm models are examined in this work, a weighted dual-site Langmuir model found in literature, a dual-site Sips model developed in this work, and an extended weighted Langmuir model also developed in this work. Parameter estimation is performed using available isotherm data and it is shown that the models are able to predict the CO2 adsorption data well. A kinetic model is then developed using a linear driving force for mass transfer which does an excellent job at predicting time dependent TGA data. An additional goal of this work is development of a chemistry-based model for functionalized solid sorbents that aims to capture the underlying adsorption reaction mechanisms which are not typically considered in solid sorbent modeling. As part of this model, optimal reaction set selection is performed since the reaction pathways for dmpn-Mg2(dobpdc) are still relatively unknown. Parameter estimation is performed, and it is found that the chemistry-based model significantly outperforms the Sips isotherm model with regards to prediction error and other model building criteria. To aid in the evaluation of the commercial feasibility of the MOF, equation-oriented mathematical models for a fixed bed contactor and moving bed contactor are developed. The contactors are then to simulate industrial scale CO2 capture process for coal based and NGCC based flue gas. Using developed cost models, techno-economic analysis and optimization of these processes is then performed and it is found that efficient thermal management can make these MOFs viable alternatives for CO2 capture processes
Localizing coalescing massive black hole binaries with gravitational waves
Massive black hole binary coalescences are prime targets for space-based
gravitational wave (GW) observatories such as {\it LISA}. GW measurements can
localize the position of a coalescing binary on the sky to an ellipse with a
major axis of a few tens of arcminutes to a few degrees, depending on source
redshift, and a minor axis which is times smaller. Neglecting weak
gravitational lensing, the GWs would also determine the source's luminosity
distance to better than percent accuracy for close sources, degrading to
several percent for more distant sources. Weak lensing cannot, in fact, be
neglected and is expected to limit the accuracy with which distances can be
fixed to errors no less than a few percent. Assuming a well-measured cosmology,
the source's redshift could be inferred with similar accuracy. GWs alone can
thus pinpoint a binary to a three-dimensional ``pixel'' which can help guide
searches for the hosts of these events. We examine the time evolution of this
pixel, studying it at merger and at several intervals before merger. One day
before merger, the major axis of the error ellipse is typically larger than its
final value by a factor of . The minor axis is larger by a factor
of , and, neglecting lensing, the error in the luminosity distance is
larger by a factor of . This large change over a short period of
time is due to spin-induced precession, which is strongest in the final days
before merger. The evolution is slower as we go back further in time. For , we find that GWs will localize a coalescing binary to within $\sim 10\
\mathrm{deg}^2$ as early as a month prior to merger and determine distance (and
hence redshift) to several percent.Comment: 30 pages, 10 figures, 5 tables. Version published in Ap
Defining the content and delivery of an intervention to Change AdhereNce to treatment in BonchiEctasis (CAN-BE): a qualitative approach incorporating the Theoretical Domains Framework, behavioural change techniques and stakeholder expert panels
BACKGROUND: Low patient adherence to treatment is associated with poorer health outcomes in bronchiectasis. We sought to use the Theoretical Domains Framework (TDF) (a framework derived from 33 psychological theories) and behavioural change techniques (BCTs) to define the content of an intervention to change patients' adherence in bronchiectasis (Stage 1 and 2) and stakeholder expert panels to define its delivery (Stage 3). METHODS: We conducted semi-structured interviews with patients with bronchiectasis about barriers and motivators to adherence to treatment and focus groups or interviews with bronchiectasis healthcare professionals (HCPs) about their ability to change patients' adherence to treatment. We coded these data to the 12 domain TDF to identify relevant domains for patients and HCPs (Stage 1). Three researchers independently mapped relevant domains for patients and HCPs to a list of 35 BCTs to identify two lists (patient and HCP) of potential BCTs for inclusion (Stage 2). We presented these lists to three expert panels (two with patients and one with HCPs/academics from across the UK). We asked panels who the intervention should target, who should deliver it, at what intensity, in what format and setting, and using which outcome measures (Stage 3). RESULTS: Eight TDF domains were perceived to influence patients' and HCPs' behaviours: Knowledge, Skills, Beliefs about capability, Beliefs about consequences, Motivation, Social influences, Behavioural regulation and Nature of behaviours (Stage 1). Twelve BCTs common to patients and HCPs were included in the intervention: Monitoring, Self-monitoring, Feedback, Action planning, Problem solving, Persuasive communication, Goal/target specified:behaviour/outcome, Information regarding behaviour/outcome, Role play, Social support and Cognitive restructuring (Stage 2). Participants thought that an individualised combination of these BCTs should be delivered to all patients, by a member of staff, over several one-to-one and/or group visits in secondary care. Efficacy should be measured using pulmonary exacerbations, hospital admissions and quality of life (Stage 3). CONCLUSIONS: Twelve BCTs form the intervention content. An individualised selection from these 12 BCTs will be delivered to all patients over several face-to-face visits in secondary care. Future research should focus on developing physical materials to aid delivery of the intervention prior to feasibility and pilot testing. If effective, this intervention may improve adherence and health outcomes for those with bronchiectasis in the future
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